I agree that true friends will stick by you no matter what. But I'm torn on whether it really matters if your friends know you are bisexual. As you yourself said, there is much potential for drama, and there's no clear benefit to you in sharing the information.
To take a bit of a contrarian view, I don't think friends need to know all the gory details of each other's sexual orientation and history. A lot of people err on the side of TMI. I've never felt that someone's sexual orientation matters all that much until and unless one is considering having sex with them.
On the other hand: If you live in a conservative, rural area, your friends' homophobia or bi-phobia probably reflects a lack of familiarity and comfort with gays and bisexuals. If these sheltered people had any idea how many of their (closeted) friends and family were gay or bisexual, it might make a world of difference in their worldview.
Reading between the lines here, I think the broader issue/concern is your lack of close friends or confidants, and your specific inability to articulate your bisexuality is just a symptom of this larger problem.
I guess if the friends are not close to begin with, my inclination would be not to divulge personal information that might push them away. But if any of them are good friends, you could try opening up, in the hopes that you might be doing your part to spread tolerance in your town.
Good luck!
Steve
